Harmonic signaling system.



H. G. WEBSTER. HARMONIC SIGNALING SYSTEM.

APPLICATION FILED 111111.11, 1912.

12,13%@54350` Patented Mar. l?, 1914.

2 SHEETS-SHEET 1.

H. G.VWBBSTER.

HARMONIG SGNALNG SYSTEM. APPLICATION FILED man. 11., 1912.

1,090,485. Pawn-ed mar. 17,1914.

i! SHEETS-SHEET 2. a

MyW

Hei/RY G. WEBSTER', 0F GHICAGG, LLINOIS.

HARMNIC SIGNALING SYSTEM.

Specieaton of Letters atent.

laytented Mor, 1"?, i914'.

To eIZZ 'whom 'it may come/Hi Be it known that Hinter lVnns'rnn, a citizen 'of tbe United States of America, and a resident of Chicago, county ofy Coeli, and State of illinois, llave invented a. new' and useful improvement in Harmonic Sig naling Systems, of which the :following is a specification.

'My invention relates to kso-calleol liar`- n'ninic selective telephone signaling systems, and has for its object an organization .haring a new and improved .method of operation over tliose of the prior art, Whereby false signals are eliminated anti greater ell'iciency is secured,

l-n prior systems, of which that disclosed in llatent'llo. 779,533, issued. January 10, 1905, to lll. lll. Dean may be regarded as sn example, tbe almost universal practice has been to employ a so-callecl multicycle generator for producing those electromagnetic impulses which serve to cause tbe actuationoi the several party-line signal bells. This outfit consists of an electric motor, to the shaft of which are fixed a plurality7 of alternating currentV clynanios, all rotating at the saine substantially `Xecl rate ont speed. Four dynainos are commonly noifirled, having` two, four, six anti eight poll respectively, and tlius delivering currents baril frequencies of 1000,'2000, 3006 :intl Li000 cycles per minute, when the speed 1000 R, P. M. '.lflie reeel-members of a set of four party-line bells in suoli a. system are, therefore,.adjusted ,for frequencies of approxin'mtely 152 33) 4and i562- cycles per secondv` resi Vetiroly. so arranged, current from tbetrfopole generator inteni'lerl to ring only tlie 1G?, cycle bell, tliat from tbe four-pole generator only the 33j;- ryele bell. that troni tbe sixspole generator onl.v llie. Cycle bell, and that from the ein; Vgpole generator only tbe lie; cycle bell.

lt. now generally recognized that systems like lliatof tbe patent above nientionetl are not truly liarnionieally selective ani'l mariniertering, and that instead each reetlf.

to currents l'roin certain of the other generators c lower frequency. 'ljliis characis reterretl to in latent 1906, to lll. l

stic uetl July 3l.

n'liieli t proposed to overcome inten l 827,087, lJean. in

tering tendency by employing a di'erent strength of current for eaclr frequency; and in Patent No. 1,008,282, issued llcvember 27, 1911,' to C. H. North, in which it is proposed to avoiel the interference by employing fre quencies no one of which' is a multiple oi any other. Both proposed remedies are objectionable,--tlie first because of-its naar#v gnal character, V,and the secondi` because within a commercially operative range suc-h non-n1ultiple frequencies cannot be secured by means of' four dynamos all connected to a common shalt and operating et the same speed of rotation. Y

The object of 'the present invention is to effect an organization in which, by reason of the employment of a new principle of opere-l tion, it is possible to operate the paitywline bells by currents vfrom generators all having the saine speed of rotation, and 4yet Withoutl having present the interfering tendency above described, it will be more :fully exm plainecl in connection with the accompanyo ing drawings, in Which- Figure 1 is a diagram of suitable electrical .circuit connections for an embodiment ofiny invention, While Figs. 2,k 3 and are plan, side and end views, respectively, of one forni 01"' harmonic bell organized in accordance therewith. Figs. 5 and 6 illustrate a dillerent arrangement of' bell also organi in accordance with my invention, ancl Y a tliagrani'lfor illustrating .the relation between ii'npressetl current and reed motion.

ln tbe prior systems above described, the reetloneniber oi each bell isinlierently responsive not only to current of that frequency for Wliicli it. has been adjusted, but also to currents which are one-half, onciliirrl. cr one-'fourth of that frequency. Tlins the. reed-member of the StB- cycle bell res'lmuds to currents from tbe 1G?, cycle generator, the cycle generato' and tbe 66%- cyele generator; tbe reed-member of the 50 cycle bell responds to currents from tbe 16?,

cycle generator and troni tbe 50 cycle gener ator, while the reeel-member of tbe 33?, cycle bell responds to currents from the 16,2, cycle generator antl trom the 33?,- cycle zgenerator. investigation shows tbat the vibrations in response to snr'li lower frequencies are true liarnionic vibrations, gradually increasing in amplitude, and (in the absence of means for limiting the strength ot' the current inipulses) causing; a' rigorous anal Fries?, y

continuing ringing of the associated he]l-,frongs` Thif characteristic of vstcnislike that in question to he :iltriliuterl to the manner iu avl'iiclr the polarized electromagnetic signal ric devices are oragnized. in. these n di a pol rized armature, forming a per. of the reednieinher of each hell, vihrates before or het-Ween the poles of an electreuiagnet energized by each frequency of V`iup; current that is impressed upon the line. lt is a Well recognized fact that if, when current impressed upon a polarH ized dci/ice ot' this character, the armature he slightly oil' center, then the armature Y will he l'tractcd toward that pole of the elcctroinagnct to which it is nearest, regard* less of the polarity of the impressed current impulse. Because of this7 when current iin Jpulses of any frequency are imprc 'sed upon the line circuit in these prior s', ns, and each reedmemher is set slightly in motion hy the initial impulse, then each succeeding impulse produces a magnetic attraction coin-- aiding in time and in direction with the natural motion of any reed-mcrnher adj usted for a frequency rate twice, three limes, or four times, the impressed frequency rate.

These attractions coincide with every second swing of the reed-member adju. ed for twice the impressed rate, with every third swing of that adjusted for three times the rate, and with every fourth swing of. that adjusted for four times the rate. ln responso to a succession of these coinciding attractions, each reed-meinber viioratcs with an increasing amplitude limited only hy the stiffness of the reed spring or by engagement with a stationary part of the device.

in the of my present application, I so organize the polarized signal receiving devices that the 'magnetism set up loy the impressed current impulses produces resultant forces acting upon the reed-tongue armature,- always in one direction for impulses of onelpolarity, and always in theoppositc direction for impulses of the other polarity. As a result, when current impulses of any frequency are impressed upon 'the clectro- .magnet of such a device having its reedmember" adjusted for twice the impressed rate, each resulting magnetic impulse may coincide in point of time with every second swing of the reedincmbcr, but does not coincide in direction. On the contrary, each magnetic force pulsation coinciding in time and in. direction with a swing of the reedmelnhcr is succeeded 'by a force pulsation coinciding in time -vvith the second succeeding;

swing, `out acting in direct opposition there i f. Coilscouently, every' second pulsat'icn ts to suppress and limit the amplitude of thc reed vibration, and the device as a Whole may he said to harmonically unresponsive to current impulses of half the'rate for which it is adjusted. This is a result which CIK lli oelieve to he broadly new in tuned reed teni under which thc rcednicmher is adjustcd for a rate four timos the impressed rate, similar results are secured. force impulse coinciding; in time with every fourth swing of the rccd-mcmhcr, acts in dil rect opposition tf such swing and .serves to supplA and limit the amplitude of .vibration. The action described in this and the preceding paragraph may he readily understood by reference to lliA 7 of the drawings. ln this figure, the spa .i .g and direction of the reed vibrations is illustrated by the curved full line, while the broken line indicai-,cs thcsmcmg and direction of thc force pulsations resulting from an impressed current of one-half the frequency for icvhich the recdniemlier is adjustedn As here indicated, over f odd numbered pulsation acts in hai`- mony with the :reed motion, While every even numbered pulsation acts in direct opposition thereto.

Under the condition of impressed altcrmating current pulsations of a frequency one third of that for which the reed-member is adjusted, harmonic response seems inherent. Every swing of the reed is opposite in direction to the third preceding swing, While every current impulse is of opposite polarity to the immediately precedin impulse; and with coincidence in point o Ltime between every impulse and every third swing, coincidence in direction of motion and of applied force necessarily follows. Operating under conditions necessarily involving magnetic leakage, and constantly changing inductance and magnetic permeability, it seems i ncvitablc that devices of the class in question should respond harmonically. under the assumed condition. This conclusion seems also true With respect to the impression of'a rate onefifth of that for which the reed-mel'nher is adjusted. To avoid such interference, l organize my improved system so that no one of the current rates employed shall be of a' frequency exactly or approximately onethird or one-fifth that of any of the other current rates employed. If desired, the low1 est rate employed may have a frequency greater than one-third the frequency of the highest rate employed, although this is not essential. For instance, the dynamos. ef the multi-cycle generator' may ne provided with four, sin, eight and' ten poles, respectively; or with six, eight, ton and twelve poles, respectively, operating in 'either case a t a speed to bring the highest frequency Within co1n mei-cial limits. Also, if de ired, one or more of the lower frequencies of the party-line system may be generated by ay machine running at a speed different from that of thc multi-cyclo sot used for giving the higher frequencies. For example, in. accordance With respect to the condition in my sys- A ma gnctic y inye'laien, Geeignete harmonie non Jence may oe Secured employing for ier frequencies e mulirevole gener-4 Jing approximately 32, e8 and e eend, and for-the lowest i' .L)- Q- en auxiliary generator giving apnaieiy L8-fg'- cyclee per second., l :im .'ecl, lieweveig ifo any perienlor of lire("neneies fer by means my on non-inerferenee is harmonie possible using many other groups of finies than liosev indicated. l. ring non" to 'Fig'. l, lia-ve iniCa-iecl nl` il; C, D and E ille subscribers sin of a. party-line rele-phone- Sjlstem or ed in eeeordance Witlrmy invention. stations are associated by means of alie 'e wires 22,.:23, and lie switches-10, il, i2,-

iland. i5, with the generator set indi- T. The generator set eo'nsisie of e e genereier ef lie type disclosed fn Talent No. 779,533 above inenltioned, and 'the auxiliary generator inclicaied et E. The meier G is governed by Ineens of the centrifugal switch 16 and Adie lielcl eireuit ,resistance l?, i operate ai Substantially con slant speed, nml ie directly coupled to lie nl'ernatng current. dynaxnos A', B, C and il". Connected by ineens or" Chain und snroelzet gearing i8, 19, 21, to' thesimft of flynnnios C and D", the auxiliary dynamo E is also driven by the motor Cr, bui it a Sneefl cliiilereni; from that' of dynamics A', il, C ind Dl. FWhile l have illustrated the muli-eyele generator an lie supplemental, (lynmno ne connected oy chain and. Sprocket gears, il"y Willibe iinclerrlood ."linib'any Conneetinp means may be employed Suitable for maintaining :i eonetfint sneed relelion be l'u'een lietwo inzieliines. The switches n'niy he of nnfy'suilelile i-yne, flint :it l5 Serving "o inerrnpl'. elle eireuiiA of the wires Q2, 2?. :mil to bring these Wiree ,into electrical nsscoeimionjuiih ille eeleei-ing ewi'relies l0, ll,

lil :nml which Serve to directly esi'lnlrlieli eonneriio with lie dynamo gener mi; D' 'flint particular frequency wliiell it is r'leeirefl lie :iinprees upon the line. The Seyerul eertli eonneelions 2G are io lie umlen sinful ne inflienlinif n suilnllle return Connf'elion eelueen ille Several su'ilieiiee und 'iw return side of ille Llynzun-os. uinlrrsi'oofl. this relurn cfoimeeiion muy lie n Elm-l mzmecl'im.. er may be :i Connection 1nrolling' ille .foiulurters leerling lo the cen- (r-,rl mlierr o!" :i fn'nnmon l'mlterySystem, ns i 4irui'ell in l'lnieni No. 779.5233. l have u-pneelv emill'ed tlieee null other details. :ea :1 ,u:ilin;; ineens for llie several S is Well U f:\\,' i l;e ille (zentral oiliee inlliinlj and Sig;-`

nnlingf connectione of the telephone line.-

wili rerlspeet to the topper iveieht il applications are inniters Weil. unfierstoefl by those skilled in the nrt. will also loe understood that at elle snlisteizions, the condenser may loe omit-eed, if desired. enel that any suitable method of conneei station apparatus may be employed. The uneil reed-members of lie sei/eifel subsi tion bells are indicated et a, Z, c., fi' incl e, nini are adjueted to respectively respoml to lie current freqneneies generated by dynfnnos li. B, C', D and F. le illnsreing; Sui'.- able frequencies to be employed lie (lynn.n mos A', E', C and'D may nave foure Six, eight and ten poles, respectively, operating :it o, speed to gire sqiproiinnleljy' "35 and 65 cycles per eeeond, in wliieli ease Ll'y'-,

nemo E Wouid be 0 any suitable design and the yznulti-eyene ygenerator may be operated lo give frequencies of 30, 45, G0 and 75 cycles ,per seeend, in which ense the auxiliary dynamo E mightproperly be e two or four pole in:xelnne generating approximately l? or nonroxinmtel Q23 cycles er second. it

will be obvious tlial; if lie-.selective operelion of but four stations is desired in the system, tl'ien either the auxiliary generator, or the len pole generator (with diev corresponding' Substnion bell) may be omitted from either arrangement aboveoutlineil; ami the speed of the dynnines and ille eorrespomling reed adjuslmeni's may be varied Clesirecl as lon-f1y as the :above .indicated relave speed relation is maintained. As :in exemple of surli :i modifica-tion, the len pole generator D and station D coule` be omitted, and generators A", B und C opent-ed io giver@ spee'tive frequenciesy of 333i', 50 und 66?;- eyclee per second. in which @nee generator E would prefernl'ily be (liberated lo zQive :l frequency ol approximately L cycles or upnroxiu'miely lil-.12 Cycles per' second. lit. will he upperenl from lire above het tile unf'ierlying i'uinciple of tliiS *phase of my inveulion is izlie avoidance of current rates wliielx are exncfl'y, oriupproxinmtely. orlll multiples, 'suoli :is one-thirrlor one-ililn oil? the fr@ queuey of any other rate.

Vllefeniing nou' to ili'e meelmnieul Sirueture of die tuned reed belief my invention. Figs. 2, 3 mul il illueirzie one inelnod nl? suitable embodiment. Fig. Q is n eine View. Fig. 3 is a Side View one Fig. l is e View of the arnmlure eml of lie device. A. meuniing plaie 25 is proi'iierl, Slow-ful :it QG. 26. for l'l'xeI reception of ilxe Jonjmestsf mul having Turned up ears Qi", 27, 52?', '2i'. Wliieli turn the iuljusimen- Serews Three serews nre threaded in ille nos s CIi in The Slot@v Q6 nml -tliue mijn-Sii' ilie gouge il() YThe eurvecl permanent magnet 3l is secured lo lle inounaing plate by bolts 44, 4%, zincl line reo its opposite poles N, S, perforatek for-'the reception of the soft iron bolts 32, ,'whose heads 33, 33, constitute adjustable pole-pieces for the permanent magnet. The armature consists of the two angular pieces '39, 39, be

A 39, at a iixed distance from the magnet ends.

The non-magnetic nuts 3l, 34,, and iron nuts .36, 36, serve to hold the pieces 35, in place; and also provide means for adjusting the bolt heads 33, with respect to thc armature 39,39, and so varying the air gap for the armature. Air gap spacers of nonmagnetic metal may be lifted in the armature or bolts, orthese parts may be plated with copperif desired. The electromagnet consists ot a single spool having` core secured at one end to the ends ofthe pieces 37, 37, by means of the screws 47 and 46, and at the other end by the screw 48 to the soft iron piece 32 carried 0n the mounting plate 'lheelectromagnet may be provided with any suitable winding, one such being of approximately 12,000 turns of No. 33 single silk covered copper wire, havinga resistance of approximately 500 ohms. The structure is one having no break in the magnetic circuit of the permanent magnet or electromagnet, except at the operating air gap of the armature. Vhen. assembled as above, the entire device constitutes a rigid unitary structure in which the armature pieces 39, the leaf-spring 50, the rod 40 and tapper weight l constitutes reed-member,

or reed-striker, having a characteristic rate f of vibration. Itis adjusted during assemcps.-

bly for currents ot predetermined frequency by varying the (mei-ating air'gap and the length and stittness ott the leaf-spring', and by varying the tappcr weight with respect to its size and to its position on the tape per rod. l

' Figs. 5 and 6 illustrate another method ot organizing the tuned reed bell ot my invention, liig. 5 being` a partial plan view, and Fig. 6 a sectional end view on the line 6-6. The mounting plate 61 corresponds to plate '25 otI Fig. 2 and is to be under stood as adjustably supporting gong-posts and gongs in a similar``manrreitx-,v yTh ermanent magnet 62 secured tothe pip-te 6.1 by bolts or screws 64, and between its two legs is mounted the electromagnet G3i The electromagnet core is secured atl one end l to the plate'61 and magnet 62 by means of the screw 65, or in any other suitable manner; and the opposite end is provided witha slot' 73, and enlarged portions 64,' 64, for supporting the reed'member. This reed- 70 member consists of the two soft iron armature pieces 72, 72, the tapper rod 66, the tapper weight 67, "and the leaf-spring 68. One end of lthe tapper rod, and one end of the leaf-spring are rigidly clamped between' 75 the armature pieces 72, by means of rivets, as indicated at 76. The other end of the leaf-spring is rigidly supported in the slot 73, betweenthe core portions 64., by means of rivets or bolts, fis-indicated at 71, 71. Non-magnetic stops maybe provided, as indicated at 70, or in any suitable manner. The end portions 69, 69, of magnet 62, con-` stitute opposite poles, and the electromagnet may have 8,000 or any other suitable 5 number of turns in its winding. As so organized, the reed-member has a characteristic rate of vibration, the magnetic circuit is practically unbroken, except at the operat ing air gap which may be givena permanent adjustment., and the device as a whole is. compact, rigid, etliciei1t,and economical to manufacture.

With the. construction of Fig. 2, or of Fig. 2' 5, when alternating currents 'are 'impressed' 5,5 upon the electromagnet winding, thearma ture always receives an active magnetic polaritv, when current flows in one direction and an active and opposite magnetic polarity when current owsin the other direction. Thus, regardless of the position of the ar-vr mature, the reed-member always receives. an active stress in one direction in response to current impulses of one polarity, and an active stress in the other direction in response to current impulses of the oppositepolarit-y. Asv thus organized, the present device has many advantages over prior tuned reed b ells, aside from those advantages already pointedy out. vOne characteristic of prior reed bells of the polarized type is found in the more v or less well knownfact that when impressing rela-tively strong current impulses' of that frequency for which the bell is' adjusted,

if the bell armature be at that instant slightly vibrating, as from a previous ring,

it willv frequently fail to respond and ring` the bell, and instead will vibrate continuouslyat small amplitude as long as the ringing circuit remains closed. This..faulty1'20 operation seems to be due to .the reed mo` tion getting into and remaining in a phase relation with respect to thevimpressed current, under which it is displaced practically one hundred and eighty degrees from that` phaserelation under which its greatest amplto pf'vibration can be secured. Its f ce is `iust :1s-'objectionable the reed-tongue remained device of the present apin man; a motionless *1 5 plication, the characteristic just flescrilieil is Wholly absent; andV instead the reed-meinloer invariably and quickly assumes its full amplitude of vibration uncler all operative conditions. The lclevice has an efficiency and s positiveness of operation not founclin any priordevices of this art, so fer as l am aware.

While I have illustrated my invention as applied to a party-line telephone system, l realize that it is applicableto'other kinds of harmonic signaling systems and (lo not limit myself to its telephonie application. llhile l have' illustrated rny invention reference to certsiin' particular signaling cur-- rent frequencies, to particular ineens for generating these frequenciesa and to particulsr mechanical arrangement of the devices acted on by these frequencies, l ern not restricted to the embodiments here set' forth, and desirel to cover any and' all inethocls of practising the invention,

lWlierever in the following claims the phrase liernionically unresponsive is enr, ploy/ed, it refers to that condition unrler which a reali-member has no tendency to increasing amplitucle of vibration in response to s, succession of impulses. Wherever itlee following claims have einployecl the term met stress or force, l wish it to he llnncerstood as referring to the resultant of e plurality of stresses or' forces acting any given instant.

ll of the alcove statements tion, have fully veriecl by actual tests. lt may also loe here pointedV out in prior harmonic signaling systems employing' .multi-cycle generators, non-interference of signals depends upon adjustments oil' onerating singen; ireed vstiiiess anal current strength. ln thel system. of the present stp-- plic'ation, non-.interference is securerl by the avoidance of frequency rotes which are odd numbererl factors (es one-third or one-iftli) of the other rates employed; and by the ein- :is to operar .ployment of reed-bells inherently harmonically unresponsive to currents having ire-f quen'cy rates which are even nurnloerel fac tors (es one-heli or onesfourth) of the frequency rates for' which they are Vadjusted.

' I claim:v j

l. A harmonic signaling ysystem compris ing sources of alternating current oi? (lia 1rent frequencies in combination with tively operated reed-bells haring rV spectively tuned to seicl frequencies n of snicl 1Dells having reefl-actuatin,er` ineens, including s. permanent megnet enti en electromsgnet5 for causing net' magnetic stresses corresponrling to the direction sini" frequency of the impressed current impulses independently of the momentary positions of the reed, whereby the reeel oli .one of seid bells is brought into coniunctive phase reine.

tion with the impresse current to cause its other ing: sources et alternating current or' 'frequencies sonic of 1which beur s substantially even multiple relation to eecli other, in conn.

binstion with selectively operated reetlliells euch lie ving reed-sctiisting ineensi including a permanent magnet :ind en electroinsg'net, for causing net magnetic stresses corre sponding to the direction end frequency of the impressed current impulses inrlepenrleutly the momentary positions of the reeel.

A harmonic signaling system comprising sources of alternating' current of requencies some of ivliicli'loeer s substantially even inultii le relstion to escli other, in conibination witli'e multiple station signs'ling circuit havin at escli station e, reeel-bell, the reeds of seid )elle being respectively tuned to respond to currents of seicl frequencies, and having at each ci certain of snirl stations reed-nctustingg ineens7 including the floell inegfnet and u. fiernienent muguet, for sans net magnetic stresses corresponding 'to the flirection end frequency of the impressed current impulses independently of the In@ harmonic signs party-line telelsteni comprising cent-rel ollrice'spproducing' signaling currents ot frees approximately 5G enti 66% .ie-s per sec-omi, other ipparetus precincre' currents oi frequency stilisiinilar to one-tliircl the frelower them' one olx the in eonihinstion with e. lepiione line having et s, ing" sigrrmli stsntisily qi'iency ci.,

i respond to currelits of A y enel haring et eecli olf certain of se y ations ,actuating ineens, in clnrling eperrnenent magnet snol an electrocausing net magnetic stresses to the clirection sind fre impressed current impulses independently or the momentary positions of the reed.

A harmonic signelingperty-line telephone system comprising cent-rel slice ep naratus producing signaling currents of iti einvencies approximatelyB3-l', 50" enel cycles 1per secondi, and other apparatus producing signaling currents ot' s. frequency substantially flissiniiler to one-third the ire selll.,se,i l bells being rellt? quency of. and lower than, any one' ezt the other frequencies, in combination with t multiple stetion tclepl'ione luie having et 'each station s reeel-bell, seid bells being ref spectively ltuned to respond to l. currents ci seifl frequencies, and having; et escli ci? certain of seit?. stations actuating ineens, irs chilling e permanent magnet en clectromagnet, responsive to the current of theti frequency to which the part .uler device 'is ,netic .polarization of its reed-ennemie,

vStricteil to prevent its operation.

`Clucing alternating nnignetic polarization of its reed-armature whereby the vibration of 'said 'l will-oncles und eucli o certain of said tuned, to bring; seid reed always into com junctive phase relation Wit-l1 the impressed current.

l5. Il liurnionie signaling syst-ein comprising: mui-wes el n rusting current. of differ ont i'iroin'fnries in roinbln:1i-ionwith .selectively i'qicrsted remi-bells having ree( l-urinuturcs; respectively tuned to said frequencies and euch of said reed-bells lim/ing means, including a permanent magnet* and an elec tronmgnet, for producing alternating mug`- whereby said 1ceil-:1rn'1ntnie receives netinngrnetic stresses comesponcling to the direction and riiquency of impressed currenty impulses independently ol the 'momentary positions of thc reed-armature und whereby the' reed-armaturc of one of said liel is brought into eonjunctive phase relu tion with the impressed current to cause .its operation and the reed-armature of the other of said bells has its amplitude of vibration reA 7. A. harmonic signaling system comprising' sources of alternating current of frcquences some of which bear e substanlialljy even multiple relation to each other, in com binationwith selectively operated reed-belli having reectarmiitnres respectively tuned to said frequencies und each ci certain of seid reed-bells having Ineens, including a perinanent magnet und on electroinugneti for prothe reed-armature is dampened lov currents of frequencies which nre even submultiples of the freq'uencj/Y eorresponding to the pei# 'tifmla r .reed ernia t ure.

8. A harmonie signaling system comprising sources of alternating current of frequenciee some of which bear a substantially even multiple relation to each other in conibimition Y'ith selective@7 operated reed-bells havin reedarmatures respectively tuned to living! re ni; its imerzttion.- A 9 A liernionlc i inning system compris- `q'in-:ncies some of which bea-r 'e substantially f even multiple relation to each other` in conv i bination 'with selectively .operated reed-bells l having reeduirmetnres respectively tuned io said frequencies and'each of certain of .seid i reed-bells having ineens, including an elecA tromagnet of which its reednrmature is l i 'roinsigi'ncl; 'for rousing net magnetic n even sulmnultiliile `ing sources of alternating current of trev` )olor-extension for eunsin currents of frel 7 I n qneneies which are even su multiples of the frequency corresponding to the particular reed-bell, to dampen the notion of its reed nt regular .intervuis to thereby7 prevent its operation. i0. A. lmrmonic signaling system cornprising u source of alternating current in combination with two reetlbclis having reednnunbers tuned to dierent rats and means for impressing' magnetic stresses upon said reed-members corresponding to the direction und frequency of the innnessed current impulses independently of the momentary position of the reeilniembers whereby the reed- 'ineinber of one of said bells is brought into conjimctive phase relation with the im pressed cin'zrent to the reed-member of the other oi said bells has its amplitude of vibration restricted to prevent- .its operation.

il. A lmrinonic signaling system comprising :i tuned reedetrilrer having n characteristic inte of vibration. ,11 source of alter outing current of :i freqin y substantially f rute. i second the sume as said characterA reed-striker tuned to u substantially different rote? and means for impressing upon said reed-strikers magnetic sire es corresponding in direction and frequency to, the Current alternations of said source indecause its operation andr pendently of their momentary .positions whereby the maximum amplitude of vibra ltion of the first mentioned reed-striker is eii'ecied to cause its operation und the :implitude of vlbrotion of sind .second reed-striker is restricted to prevent its opsrution.

i2. A lizunimlic pnrtydii'w telephone sys teni comprising (.entrfii/.oi'iiixi omgeruim producing signaling currents of 'fri-uiufn'cies, some of which bear :in eren sull-multiple relation to @ech other :imi none oi. which nrc oddsulnnultiples oilw mlm-:1r in combination with u multiple simi :o :eleplionr line lniviupj'zit euch station u ri wif ell, suoi .bells spectively tuned to ses) lo cur- )on rents o titl frequencies und having;- u? oit certain oit said stations actuating' un includ'.

i, ng' u permanent magnet and :an cleorusses rorrespoiidling to the direction and frequency' of the iifiprcssed current impulses independently ot tlie momentary positions of the reed. 13. lnui'nonie signnling s fstezn com; prising; sources of alterna ting curreu frequenries ofi' Whirli :-:on'ie liffiar subsi i to 'eecli other.. :some fire lion-:nonnina o' others und none` ure odd multigges of otl'ifrs in combination jnitli ii'iultiple station telephone. linel lluvingr, :it will station a reed-Abell, said bells being; rl tively timed to respoi'ul to currents nl' vid freqneificifr;` und haring ut tin', [iig-lier: :uned ol those :'i'uiions tuned to 1e spend ik tlie frequencies bearing the even ying sources of alternating current of frequencies of which some bear a substantially even sub-multiple relation to each other, some are .nonmiultiples of otherszand ,none

are odd multiples of others, in combination A with selectively operated reed-bells, of which the higher tuned ot those bells correspond ing to the frequencies bearing the even multiple relation, has reedsaetuatin'g means for causing net magnetic stresses corresponding to the direction and frequency of the impressed current irnpulses independently of the momentary positions of the reed.

15. A harmonic signaling system compris-- ing sources of alternating current of frequencies of which some bear a substantially even sub-multiple relation to each other, some are non-multiples of others and none are o'dd multiples ot' others, in combination y with a plurality' of reed-bells having reedmeinbers tuned respectively to said frequencies, and means associated with the higher tuned of vthose reed-members which are tuned to the even multiple frequencies for impressing magnetic stresses upon said reerlmembers corresponding to the direction and frequeneyfof the impressed currentimpulses independently ofr the momentary position of said reed-members, whereby Whenever current of a frequency suited to one of said even multiple reed-members is impressed, said reed-member is brought into eonjunctive phase relation with the current to cause the operation of its bell and the remaining even multiple reed-members are restricted in vibration to prevent the operation of their bells. d f v 16. A harmonie signaling system comprising'sources of alternating current of fre` queneies of Wliiehsonie bear a substantially even multiple relation to each other, some i are non-multiple of others 'and none are eddy multiples of others, and selectively operated reed-bells respectively tuned to said fre-- quencies and responsive only to their respective frequencies.'A i A .In Witness Whereo hereunto' subscribe my naine this 9th day of March, 1912.

HARRY o. WEBSTER. 

